Flexible wings 2011

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djos
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Joined: 19 May 2006, 06:09
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Re: Flexible wings 2011

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You guy's are barking up the wrong tree, the wing obviously flexes a bit but it's mostly an optical illusion caused by the amount of rake RBR run:

Image

You can see the diffuser is significantly higher off the ground than the MacMerc in front and the actual front wing height looks pretty similar on this angle.
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mx_tifoso
mx_tifoso
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Re: Flexible wings 2011

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What doesn't work in your observation Djos is that the McLaren is exiting the curve while the RBR is halfway in. The McLaren is accelerating thus squatting, while the RBR is still diving thus the differences in diffuser height. IMO.

The screenshots of the RBR and Ferrari in the same section of the straight prove that their front wings do flex more than the rest. It's hardly an arguable subject at this point in time.
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djos
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Re: Flexible wings 2011

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mx_tifosi wrote:What doesn't work in your observation Djos is that the McLaren is exiting the curve while the RBR is halfway in. The McLaren is accelerating thus squatting, while the RBR is still diving thus the differences in diffuser height. IMO.

The screenshots of the RBR and Ferrari in the same section of the straight prove that their front wings do flex more than the rest. It's hardly an arguable subject at this point in time.
Hmm, I guess my pic merely confirms the RB7 has very soft suspension then?
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mx_tifoso
mx_tifoso
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Re: Flexible wings 2011

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Possibly so, or that McLaren is wasting valuable real estate on their rear wing by not having a sponsor logo on it. :mrgreen:
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Formula None
Formula None
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Re: Flexible wings 2011

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They've a sponsor, its subliminal though:

Image

marcush.
marcush.
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Joined: 09 Mar 2004, 16:55

Re: Flexible wings 2011

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RB need to run more rake to counter the huge downforce their bendy front wing generates.
As the leading edge of the stepplane basically is the contact point but the hinge point is the front tyrefootprints lots of negative camber (softer suspension as you ride only one sidewall)and softer front suspension would not allow you to run more rake without actually raising the front of the car....so you´d nee to run the car considerably higher than others.
Somewhere the RedBull cars of late differ in their interpretation and exploitation of the basic set of rules ..i think it has to do with reference and stepplane tolerances but also with a certain behaviour of the underfloor under load.
The behaviour of the wings is elastic deformation ....as it returns back to its original position when stationary.No plastics no chemical reactions ,just simple applied physics with fibre orientation and clever design.The wing and nose react to the forces not in the way a piece of isotropic material of the same physical shape would do.Nothing new or spectacular there.

bot6
bot6
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Joined: 02 Mar 2011, 19:30

Re: Flexible wings 2011

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Any plastic or semi-permanent deformation is explicitly forbidden by the rules, so I doubt Red Bull would go for that. It's elastic deformation, but it is non-linear thanks to carefully laid down carbon fibers.

I'm really starting to wonder what the hell the FIA is doing. That wing brakes the rules and the photos show as much. Even if it passes the bending test, it breaches the "no bridge with the ground" rule and the "reference plane" rule.

The whole "perspective can be decieving" thing is outdated, there are ways to reverse engineer a shape from a photograph using basic optics theory. Everyone talks about it... except the FIA. And it seems the other teams are not willing to protest.

The question is why? Why would it be in their interest to let one or two teams cheat?

shelly
shelly
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Joined: 05 May 2009, 12:18

Re: Flexible wings 2011

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Ciro Pabón wrote:You don't have to change angles of attack (even if they change) to get an advantage of the front wing bending. Just the diminished ride height is enough to provide you more downforce.
I agree with you. However, some pics posted here seem to show that rbr front wing has an higher incidence than what coming from car body rake. I think it could be either of these two:
-incidence increase is a side effect coming from the twist-bend coupling needed to be flexible but rule-compliant
-the wing in the not-flexed position is in a off-design condition, and rotation is required to get to design point (you can fit bigger section in the mandatory endplate rectangle if you raise leading edge, then twisting will adjust incidence to design point)
Ciro Pabón wrote:About why other teams haven caught up with RBR, I insist that the trick needs a wing that is not elastic, but plastic or thixotropic. That must be quite a trick and requires research.
Agree with you that other teams seem not to be on the same level of mastery (hiding in the word mastery everything from trickery to top end technology); seems very strange to me that they have not found a way to reach the same level (considering also that a lot of people change team every year).
I disagree on it being plastic; maybe it could be thixotropic. I recall a nice thread for last year about dampers that can lower the car as a consequence of excitement frequency.
Maybe it is nothing so exotic, like bot6 suggests: it is an elastic anisotropic non-linear cantilever beam (lots of academic research is available on the subject).
Agree with marekk that a big advantage in front downforce has to be compensated with a similar gain in rear downforce, which could be difficult to get; but as for now we do not know if total downforce is rear limited or front limited in rbr chasers' car; in fact domenicali told the press they are lacking front wing downforce compared to what they expected from wind tunnel.
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marcush.
marcush.
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Re: Flexible wings 2011

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but:rake will also give you a downforce peak at the leading edge of the tea tray...and Vetel chose to run a lot of the time with the drs deployed so the car seems to be planted at the rear as well....

marekk
marekk
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Joined: 12 Feb 2011, 00:29

Re: Flexible wings 2011

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We have to look at the whole car.
More downforce on the FW means more upward bending of the flow, so you have to position the rear higher (more rake). But with more rake you loose diffusers efficiency and you have to compensate for this with tight rear packaging / blowing diffuser / more rear wing.
You can't just add flexi wing to your current car and go 1s quicker.
This concept works really well only in quick corners as we see - and is very hard to simulate cornering car's behavior in wind tunnel (not to mention revolutionary "only CFD" way as in Virgin).
Lacking any spare test time, teams are hardly able to catch RB's years of experience.

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horse
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Re: Flexible wings 2011

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marekk wrote:But with more rake you loose diffusers efficiency...
Could you explain a little more about what you mean there marekk? Do you mean that the pressure distribution is changing with more rake? More to the leading edge of the floor and less to the diffuser? Overall though, with extra rake angle you'll get extra DF from the floor, right?
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marekk
marekk
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Re: Flexible wings 2011

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marcush. wrote:but:rake will also give you a downforce peak at the leading edge of the tea tray...and Vetel chose to run a lot of the time with the drs deployed so the car seems to be planted at the rear as well....
I think RB7's DRS is designed, like the whole car, with pole position and lap time in mind - they don't bother that much with DRS as overtaking device, and they loose not that much downforce/drag with DRS activated.

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raymondu999
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Joined: 04 Feb 2010, 07:31

Re: Flexible wings 2011

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To maximise romping away from pole though, they'll have to reduce the DRS advantage they have. A no-DRS car will be faster in the race than one with DRS, if there is no time where the guy releases his wing
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marekk
marekk
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Joined: 12 Feb 2011, 00:29

Re: Flexible wings 2011

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horse wrote:
marekk wrote:But with more rake you loose diffusers efficiency...
Could you explain a little more about what you mean there marekk? Do you mean that the pressure distribution is changing with more rake? More to the leading edge of the floor and less to the diffuser? Overall though, with extra rake angle you'll get extra DF from the floor, right?
More rake = more downforce at floor's leading edge for sure, but less at diffuser's leading edge (bigger gap to the tarmac = less speedup of the flow).
And diffuser is by far more powerfull than front of the floor, so nett loss of downforce IMO.

shelly
shelly
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Re: Flexible wings 2011

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Let us not consider rake only, but fornt and rear ride height.

IIRC, a well performing car form an aerodynamic point of view develops more front downforce when reducing front ride height and more rear downforce when reducing rear height.
You cannot go low flat (i.e. no rake), because you will loose too much energy and stall the diffuser.
So a high downforce configuration is with low front and medium low rear, thus with significant rake.

That puts again in the picture tea-tray flexing.
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